The project investigates the effects of a variety of types of insults including circulatory arrest, arterial hypotension, hypoxia, asphyxia, cyanide intoxication, and exposure to carbon monoxide on the juvenile rhesus monkey. Alterations in cardiovascular performance and nervous system activity are examined during the insult and the occurrence of patterns of brain injury later determined by examination of brain specimens. The animals are resuscitated and maintained for up to several weeks to determine the long-term alterations in brain morphology. Where patterns of pathology occur, they are carefully delineated and their relation to patterns of injury produced in the human defined. The major effort is to define the pathophysiology and pathogenesis of specific patterns of brain pathology using animal experimental models.